Perio
d
ic maintenance an
d
a
d
justment
6-9
6
4. Remove the spark plug as shown,
with the spark plug wrench includ-
ed in the owner’s tool kit.
To check the spark plu
g
1. Check that the porcelain insulator
around the center electrode of the
spark plug is a medium-to-light
tan (the ideal color when the vehi-
cle is ridden normally).
TIP
If the spark plug shows a distinctly dif-
ferent color, the engine could be oper-
ating improperly. Do not attempt to
diagnose such problems yourself. In-
stead, have a Yamaha dealer check
the vehicle.
2. Check the spark plug for electrode
erosion and excessive carbon or
other deposits, and replace it if
necessary.
3. Measure the spark plug gap with a
wire thickness gauge and, if nec-
essary, adjust the gap to specifi-
cation.
To install the spark plu
g
1. Clean the surface of the spark
plug gasket and its mating sur-
face, and then wipe off any grime
from the spark plug threads.
2. Install the spark plug with the
spark plug wrench, and then tight-
en it to the specified torque.
TIP
If a torque wrench is not available
when installing a spark plug, a good
estimate of the correct torque is 1/4–
1/2 turn past finger tight. However, the
spark plug should be tightened to the
specified torque as soon as possible.
3. Install the spark plug cap.
TIP
Install the spark plug cap so that it is
positioned as shown in the illustration
and the spark plug lead does not con-
tact any surrounding parts.
1. Spark plug wrench
1
Specifie
d
spark plu
g
:
NGK/CPR8EA-9
1. Spark plug gap
Spark plu
g
g
ap:
0.8–0.9 mm (0.031–0.035 in)
Ti
g
htenin
g
torque:
Spark plug:
13 Nm (1.3 m·kgf, 9.4 ft·lbf)
U2DSE0E0.book Page 9 Thursday, March 19, 2015 10:34 AM
